Your first batch

In this tutorial you'll render 5 personalized videos from an EffectCraft template and a CSV file in under 10 minutes.

Prerequisites

• Node.js 20+ — node --version should show v20.x.x or higher
• EffectCraft 0.8.0 — installed (includes effectcraft-cli)
• lakreet-swarm — installed globally or run via npx

# Verify Node
node --version
# v20.18.0 (or higher)

# Verify lakreet-swarm
lakreet-swarm --version
# 0.2.0

Step 1: Get the example files

Clone the repo to get the example template and CSV:

git clone https://github.com/Lakreet/lakreet-swarm.git
cd lakreet-swarm

You now have:

• examples/title2.ectemplate — EffectCraft template with two controls: Source Text (text) and Opacity (slider)
• examples/data.csv — 5 rows of data

Step 2: Validate before rendering

Run check to catch data problems before any rendering starts:

lakreet-swarm check --template examples/title2.ectemplate --data examples/data.csv

Expected output:

OK
  template:  examples/title2.ectemplate
  controls:  2 (Source Text, Opacity)
  data:      examples/data.csv
  rows:      5 valid

Exit code 0 = all good. If you see errors, fix the CSV and re-run.

Step 3: Render the batch

lakreet-swarm render --template examples/title2.ectemplate --data examples/data.csv

What happens:

• Progress bar (Pac-Man style) with ETA
• One video per row → out/1-Budi.mp4, out/2-Sari.mp4, etc.
• Summary at the end

Example output:

Rendering 5 row(s) with /path/to/effectcraft-cli
████████████████████ 100%  [5/5] 5-A_B  0s
Done: 5 succeeded, 0 failed, 0 skipped.

Step 4: Inspect the output

ls out/
# 1-Budi.mp4  2-Sari.mp4  3-Andi.mp4  4-Rina.mp4  5-A_B.mp4

Open any file to verify the personalized text and opacity.

Step 5: Read the report

Every render writes a machine-readable report:

cat out/report.json | jq .

Key fields:

• summary: total, succeeded, failed, skipped
• rows[]: per-row status, output path, seconds, error (if any)

{
  "tool": "lakreet-swarm",
  "version": "0.2.0",
  "template": "examples/title2.ectemplate",
  "data": "examples/data.csv",
  "summary": { "total": 5, "succeeded": 5, "failed": 0, "skipped": 0 },
  "rows": [
    { "index": 1, "where": "line 2", "status": "ok", "output": "out/1-Budi.mp4", "seconds": 15.5, "error": null },
    ...
  ]
}

Also available: out/report.csv for spreadsheets.

What you learned

Concept	Command
Validate data first	lakreet-swarm check
Render batch	lakreet-swarm render
Naming pattern	{index}-{first} (default)
Reports	report.json + report.csv

Next steps

• Prepare a CSV — delimiter, quoting, BOM, line numbers in errors
• Validate first — catch problems before render
• Make a template — create your own EffectCraft template